Telephone substation ringer



Patented Nov. 21, 1944 UNITED STATES PATEN' TELEPHONE sUBsTATIon RINGER l Frank J. Stehlik, Cicero, mgana Fred Schumann, Nashville, Tenn.', assignors to Kellogg Switchboard and Supply, Company, Chicago, IlL, a corporation of Illinois W i Application Nouemberfl, 1942, Serial No 465L052 p 3 Claims. (01. 116-149) This invention relates to telephone substation ringers. The general object is to provide a satis{ factory ringer sufliciently compact to enable it Jto be housed in the space available in self-contained telephone sets not using a separate ringer box, which is nevertheless capable Of giving a suificientlyloud signal.

. Onespeciflc object is to provide newand improved devices for intensifyingthe sound emitted by the comparatively small gongs of thecompact ringer. p i i I Another specific object is to provide means .for reliably maintaini'ngthe rotational adjustmentor the loosely mounted eccentric gongs.

In attainingthe firstnamed specific object of the" invention, applicants have provided a new and improved device which they have termed a reflector-resonator, in which i the sound-intesifying effect of a reflector of the general type disclosed in Eaton Patent No. 2,156,842. issued May 2, 1939, is combined with .a closed-chamber resonator having its operative opening at thebottom of the pocket com-prising the reflector. One

example of a simple, closed-chamber resonator is disclosed in the Morton Patent No.2,216.956, issued October 8,:1940.

In carrying out the second-named specific ob jeot of the invention, applicants have provided aresilient, rockable mounting arrangement for each of the gongs, and haveprovided a fixedpin which, when the gong. is in a desired position of adjustment, extends ashort distance, into one" hole of a circular rowin the base of the. gong.

The gong is thus eifectively retained against rotation, but may .be turned readily to a desired newposition by tipping the gong sidewise about its resilient mounting to enable the above-mentioned retaining pin to clear the bottom of the comprising Figs. 1 to athey show different views 3 of a telephone substation ringer constructed in 1 accordance with the features of the invention to enable the invention to be'understood.

Fig. 1 is a top view Of'thB improved ringer; Fig. 2 is a front view; u Fig. 3 i593. bottom view; and

1; Pole pieces 4 and 5 are held against the rear of magnet I by the non-magnetic brackets 42 .and 43, retained by. screws passing through the pole pieces 4 and 5. The other ends of the brackets 42 and 43 are secured to the rear ends of electromagnets 2 and 3, as seen best in Fig. 1. The front ends of electromagnets 2 and 3 are held together by the return yoke I2, as seen best I extensions Band 14 of; return yokelZ. Therear in Fig. 3. The return yoke IZ has the mounting brackets l3 and I4 formed integrally therewith;

and provided with tapped openings 15 and I6,

I through which the ringer can be secured in place. The front end of permanent magnet l is held fixedly to the return yoke I2 by screw 4|.

The ringer disclosed is of the so-called tuned type. It has a clapper 20 attached to the front end of the clapp r rodl9, assembled with arma-,

ture 1. Armature 1 isclamped tothe front end of steel mounting spring 6, the rear end of which is clamped between the permanent-magnet pole pieces 4 and 5.

l Armature 1 is acted upon by electromagnets 2 I and 3', through pole pieces 8 ands, across the illustrated air gaps l0 and II to. cause a comparatively vigorousmovement ofrod I 9 and clapportion of each of the brackets l1 and i8 is widened somewhat to permit the opening there through (not shown) to be slotted longitudinally to permit the average spacing between the eccentric gongs 2| and to the size of the" clapper 2!] used in a. given case and according to the desired stroke of the clapper. .The adjustment thus obtained is approximate and is set during manufacture by the tightening 0f the screws holding the brackets l1 and l8 and does not need to be changed thereafter because of the ready adjustment which may be i made of the eccentric gongs without use of tools, as will be pointed out hereinafter. l

Fig. 4 is a sectional. view .takenalong the line 4--4 of Fig. 1.

The driving assembly of the ringer includes a permanent magnet I, seen best in Fig.1 3, and a pair of electromagnetsZ and 3, seen best in Fig.

The resilient, rockable-mounting provided for 1 the gongsis shown best in connection with gong23 infFig. 4. A shoulder screw 33, on which a washer 34 is first placed, is passed through the some,-

' what eccentric (opening in the bottom of gong 22; and thence through the piral spring 24, and

is turned into the tapped opening inbracket l8 1 until it comes to a stop against its shoulder por- T OFFICE 22 to be varied according associated gong.

- member.

illustrated level position against washer 34. has been found that a loose mounting of this general character permits a gong to vibrate more vigorously and more enduringly than does the same gong when clamped tightly, as by an ordinary screw mounting.

It has been found that when the strength of the spring 24 is just reliably sufficient to hold the gong in place without compressing it too tightly, the gong tends to rotate out of its adjusted position. Such rotation is effectively prevented in the disclosed structure by providing each of the brackets H and IS with a short pinextending into one of the holes 25 in the bottom of the gongs 2i and 22. The retaining pin 35 for the gong-22 is shown in Figs. 1 and 4. This pin is sufficiently long to efiectively engage the gong and prevent its rotation during the ringing action, but is sufllciently short that the bottom of the gong 22 clears the upper end of the pin when the gong is rocked, or tipped, sideways against 'the leveling action of spring 24. The gong 22 may thus be rotated to bring the side of it nearer to or farther from the normal position of clapper 25, by virtue of the somewhat eccentric location of its mounting hole through which screw 33 passes.

When the desired new position of the gong 22 is reached, the gong is released and the pin 25 allowed to pass freely into the nearest of the sound-escape openings 25 in the base of the gong,

whereby the gong is effectively held against rotation out of the desired new position of adjustshown in side view in Fig. 4, taken along the line 44 of Fig. 1.

Each of the reflector-resonators comprises a main outer shell and an inner member cooperating with the main portion to define the reflector pocket and the resonating chamber. The inner portion 31 of the device 2% is shown in Fig. 2, while the inner portion 38 of the device 21 is shown in Figs. 3 and 4.

Each of the main body portions 26 and 21 forms a pocket encompassing a portion'of the It has an arcuate sideportion comprising apart of a cylinder, together with two flat end portions. The end portions of device 27 are shown at 28 and 29 (Figs. 3 and 4).

Each of the inner members is essentially arouate, and mounted substantially concentric with the arcuate portion of the corresponding outer As seen best in Fig. 3, the inner member 38 has its front and rear extremities bent outwardly to contact and overlie the corresponding portions of the'rnain structure 21 to define an arcuate resonator chamber 52. All points of contact between inner member 38 and the main body portion 2'! are preferably tightly sealed, as by solder or cement, closing the chamber 52 (Fig. 3) at all points except at the opening 40 (Figs. 3 and 4), which is located at the bottom of the reflector pocket. Similarly, the resonator opening 39 of the chamber 5| (Fig. 2) is located at the bottom of the reflector pocket of the reflector-resonator 26.

The devices 26 and 21 may be held in place on the side extensions at the front ends of the tion. Spring 24 normally holds the gong 22 in the brackets H and I3, as by being spot-welded, such as is intended to be indicated at 30 in Fig. 3 for the device 26.

The top plate 3| is useful in rigidifying the structure, in that it connects the devices 26 and reflector pocket encompasses about one-third of the perimeter of the associated gong and is located centrally about a point substantially opposite the point struck by the clapper. It is also desirable that the fundamental frequency emitted by the gong be substantially the frequency at which the associated chamber (5| or 52) is resonant. Under this condition, the reflector pocket collects and transmits sound to theassociated resonator opening (39 or 4%), whereupon that sound is greatly intensified by the actionwithin the resonating chamber and the intensified sound is then delivered out of the reflector pocket to the general space surrounding the gongs. .The volume of sound emitted during operation of the ringer is very much greater with the reflector-resonator combination disclosed than it is with either a reflector or with a resonator having no sound-pocketing reflector.

The actions of reflecting and resonating combine to aid each other. The reflector pocket tends to collect and return the in-phase sound waves emitted at one of the quadrants of the gong. The mouth of the resonatin chamber, by being located at the bottom of the reflector, operates at the most intense point of sound within the reflector and thus the resonator is markedly more efficient than is one whose opening is not provided with already intensified sound waves. The sound Waves reenforced by the resonant action of the resonating chamber are supplied into the reflector and are thereby caused to be returned from the reflector to the general area surrounding the gong, in phase with the directly reflected sound waves.

We claim:

1. A sound intensifier for use adjacent one side of a bell-shaped gong, said intensifier in-- cLuding an outer wall conforming generally to the contour of the adjacent side'of said gong and located generally concentric with the axis of the gong, and an inner wall located between the gong and the outer wall and joined to the latter to form (a chamber resonant to sound waves emitted by the gong, said inner wall having a sound-wave passage therethrough facing the gong and leading into the chamber.

2. A sound intensifier for use adjacent one side of a bell-shaped gong, said intensifier including an outer 'Wall having a generally cylindrical side portion located generally concentric with the axis of the gong, said outer wall having endportions extending inwardly from the first-named portion toward said axis to completely encompass aside portion of the gong within the pocket formed by such wall, and an inner wall located between the gong and the first-named portion of the outer wall and joined to the outer wall to form a chamber resonant to sound waves emitted by the gong, said inner wall having a sound-wave passage therethrough facing the gong and leader, a support, said gong being loosely and rockably mounted on said support for rotational adjustment about an axis eccentric with the axis of the gong, the gong having angularly spaced openings through the base thereof, and an adjustment-retaining pin fixed to said support and normally extending into any one of said openings to maintain the desired adjustment, the

opening into which the pin extends depending gon clears the end of it when the gong is rocked j gong, said pin being sufficiently short that the about its said mounting {pursuant to rotational adjustment to bring another opening into association with said pin.

FRED SCHUMANN;

upon the rotational position of adjustment of the FRANK 'J. STEHLIK. r 

